Unlock iPhone 4 iOS 5?

[DigitalCancer]

So...I was thinking of getting my wife an iPhone 4 pretty soon but we're on Tmobile service.

Is it possible to cut my sim card and unlock/jb the iPhone 4? I've tried to read up but I can't seem to find specifics that I need to look for like...modem firmware/baseband...os version that it needs to be. Also...do I HAVE to have the Gevey sim to unlock? So confused...the iPhone 3G was MUCH easier.

Thanks guys!

Moved from OT to ATA
-ViRGE

 

[Tyranicus]

It is not possible to unlock an iPhone 4 if it has the latest baseband installed.

 

[jalaram]

1) Ultrasn0w: It's getting very hard to find an iPhone with the proper baseband to unlock it with this software. Ultrasn0w IIRC needs 1.59.00.
2) Another option is to get a gevey ultra sim. Check out applenberry.com (Link) and it'll tell you which basebands you need to have to use it.
3) You can get a factory unlocked iPhone 4 or 4s. Simplest and most expensive.

Remember, you will only get edge speeds on T-Mo.

T-Mo does sell micro SIMs. Sim cutters are also pretty cheap at Amazon and applenberry.